package org.hamcrest;

import java.io.IOException;

/**
 * A {@link Description} that is stored as a string.
 */
public class StringDescription extends BaseDescription {
	private final Appendable out;

	public StringDescription() {
		this(new StringBuilder());
	}

	public StringDescription(Appendable out) {
		this.out = out;
	}

	/**
	 * Return the description of a {@link SelfDescribing} object as a String.
	 * 
	 * @param selfDescribing
	 *   The object to be described.
	 * @return
	 *   The description of the object.
	 */
	public static String toString(SelfDescribing value) {
		return new StringDescription().appendDescriptionOf(value).toString();
	}

	/**
	 * Alias for {@link #toString(SelfDescribing)}.
	 */
	public static String asString(SelfDescribing selfDescribing) {
		return toString(selfDescribing);
	}

	@Override
	protected void append(String str) {
		try {
			out.append(str);
		} catch (IOException e) {
			throw new RuntimeException("Could not write description", e);
		}
	}

	@Override
	protected void append(char c) {
		try {
			out.append(c);
		} catch (IOException e) {
			throw new RuntimeException("Could not write description", e);
		}
	}

	/**
	 * Returns the description as a string.
	 */
	@Override
	public String toString() {
		return out.toString();
	}
}
